If you want comfortable cows, bed with sand.
However, following that "gold standard" for cow comfort also means having to deal with management challenges. Some of those include sand kicked out of the stall, cows digging holes in the sand, and handling sand-laden manure. Although each challenge is unique, sand-saving devices can help lessen these problems when used properly.
Sand-saving devices fall into two main categories - those with webbing or cells that you fill and cover with sand, and those which are solid fabric or mattresses that you anchor into the stall and then cover with sand.
Researchers at the University of Georgia's Tifton Dairy Research Center have been evaluating four commercially available sand-saving devices. Following the manufacturers' installation instructions, they fitted free-stalls at the dairy with the devices, and then compared their use to control stalls that were all sand. Here's what six months' of use has taught them so far.
Any stall bed - no matter what type of bedding you use - requires regular maintenance. With sand-bedded free-stalls, it means daily maintenance to clean and remove wet and dirty sand, fill in holes, maintain the slope of the bed, and add additional sand to maintain cow comfort.
When it comes to maintenance, sand-saving devices offer some definite advantages, says John Bernard, lead researcher and associate professor of dairy nutrition and management at the University of Georgia. For example, in stalls fitted with the sand-saving devices:
- It's easier to maintain the slope of the bed compared to stalls without the sand-saving devices.
- Cows cannot dig deep holes.
- Daily maintenance is reduced by five to 10 seconds per stall, on average. Although that doesn't seem like much, five seconds per stall in a 1,000-stall barn adds up to a time savings of 83 minutes each day. And that becomes 83 minutes that an employee could spend watching for heats or cleaning waterers.
The one drawback to sand-saving devices is that they hinder the use of certain grooming devices. Mechanical devices that level the sand work fine. However, mechanical tools that dig into the bed in order to fluff the beds tend to dislodge or tear out the sand-saving devices.
When you walk through the barn and observe whether the cows are lying down or not, you really can't tell a difference between stalls that are fitted with the sand-saving devices and those that aren't, says Bernard.
Sure, some difference in cow acceptance exists, depending on whether the stalls are in the sun or in the shade. But when you compare stalls in the same section of the barn, cows' acceptance is pretty much the same regardless of whether the stalls are fitted with sand-savers or not.
This is the area that producers care about the most. If you can reduce sand usage, you can reduce money spent on sand, along with the wear and tear on manure-handling equipment.
Although sand usage varies from dairy to dairy, researchers estimate that you will need about 50 pounds of sand per stall per day, as an industry average.
Initial results from the research gives the edge to sand-saving devices with cells or webbing that allow you to fill the "holes" with sand and then cover the whole thing with a layer of sand. The two products of this design had an average daily sand usage of 28.5 pounds per day, compared to 41.15 pounds, on average, for products that have a fabric layer or mattress overlaid by sand. (The manufacturer of the mattress product has since changed its installation guidelines, which could change sand usage.)
Sand-saving devices are still relatively new. As producers start using them, more is learned about how to manage them correctly.
One thing the research makes clear: Sand-saving devices do offer some advantages that are worth considering.
Using recycled sand
In addition to comparing sand-saving devices, researchers at the Tifton Research Dairy in Georgia also compared recycled sand to fresh sand. Specifically, they were looking at the organic content in recycled sand.
After one year of study with recycled sand, here's what they learned:
- You do see some increase in bacteria counts - especially during high temperatures when misters or sprinklers are running. However, with good management, the increase is not enough to cause increased mastitis. And the increase is generally in bacillus organisms that do not generally cause mastitis.
- Recycled sand averaged 1.2 percent organic content when put into the stalls. Fresh sand averaged 0.6 percent organic content.
- Just before re-bedding each week, the organic content of the sand in the back half of the stalls was tested. The organic content in the recycled sand only climbed to 1.9 percent. The organic content of the fresh sand climbed to 1.3 percent.
- As long as you keep the organic content in recycled sand below 2 percent, you can continue to recycle it and use it as a bedding source.
- Researchers have not seen any differences in udder health between cows bedded with recycled sand and those bedded with fresh sand.